Optically controlled meta-material phased array antenna system

ABSTRACT

A system includes a base station. The base station includes: a laser assembly that transmits an optical control beam to a phased array antenna external to and remote from the base station; and a radio frequency (RF) transceiver that transmits a radio signal to the phased array antenna. The phased array antenna deflects the radio signal arriving at the phased array antenna in a particular direction indicated by the optical control beam. The particular direction of the deflected radio signal is toward a particular user device.

RELATED APPLICATION

This application is a divisional of U.S. patent application Ser. No.15/419,041 filed on Jan. 30, 2017, the disclosure of which is herebyincorporated herein by reference in its entirety.

BACKGROUND INFORMATION

In advanced networks like 5G, mobile devices may communicate overchannels at high wave frequencies (e.g., 14 Gigahertz or higher). Atthese frequencies, however, signals suffer high path loss, particularlyfor indoor coverage. Accordingly, wireless service providers thatimplement advanced networks may need to increase cell density, reducinginter-site distances to a range of about 200˜300 meters.

For the service providers, increasing cell density means increasingcapital and expense budgets, and hence, lower return on investment(ROI). In addition, if advanced cell sites are built like traditionalcell sites (e.g., macro and small cells), the service providers arelikely to see increased operational expenditure (OPEX) (e.g., towerrent, fiber backhaul maintenance, etc.).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an overview of an exemplary environment in whichconcepts described herein may be implemented;

FIG. 2 illustrates an exemplary optically controlled meta-materialphased array (OCMPA) antenna system whose components are depicted inFIG. 1;

FIG. 3 illustrates exemplary components of an exemplary OCMPA antenna ofFIGS. 1 and 2;

FIG. 4A is a functional diagram of exemplary phase delay elements of theOCMPA antenna of FIGS. 1-3;

FIGS. 4B and 4C illustrate exemplary positions of photodiodes of FIG.4A;

FIGS. 5A-5D illustrate distributions of optical energy over the rearsurface of a OCMPA antenna of FIGS. 1-3 and 4A-4C;

FIG. 6 illustrates exemplary optical components of the OCMPA antennasystem of FIG. 2;

FIGS. 7-9 illustrate exemplary use cases for the OCMPA antenna system ofFIG. 2; and

FIG. 10 is a flow diagram of an exemplary process that is associatedwith the OCMPA antenna system of FIG. 1.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The following detailed description refers to the accompanying drawings.The same reference numbers in different drawings may identify the sameor similar elements.

As used herein, the term “metamaterial” or “meta-material” may refer toa synthetic material designed to have properties not found in nature.For example, a meta-material may include a repeating/recurring structureon its surface, such that electromagnetic waves arriving at the surfacemay interact with the meta-material. The scale of each of the structuresmay be on the order of the wavelengths of the received electromagneticwaves.

In the following, an optically controlled meta-material phased array(OCMPA) antenna system includes: a base station; and at least onepassive, reconfigurable OCMPA antennas (also herein referred to as“reflector,” “reflector antenna,” “deflector,” or “deflector antenna”).In operation, the base station transmits a signal (e.g., a radio signal)and an optical control beam to one of the OCMPA antennas. The OCMPAantenna relays the signal to the user device. The optical control beamfrom the base station controls the direction at which the OCMPA antennasteers the signal.

OCMPA antennas can be deployed incrementally, to avoid a large, upfrontcapital expenditure. An OCMPA antenna uses meta-material technology todynamically change its antenna characteristics. OCMPA antennas arepassive devices that operate in millimeter (mm)-wave frequencies, andmay be constructed to be small and light. This allows OCMPA antennas tobe located where traditional cell sites cannot be positioned, as well asreduce rent (e.g., for tower space and weight, for ground space at cellsites). In some embodiments, no fiber is needed to control or sendsignals to OCMPA antennas.

FIG. 1 illustrates an overview of an exemplary environment 100 in whichOCMPA antenna system described herein may be implemented. As shown,environment 100 may include a network 102, a radio mount 106, an OCMPAantenna mount 108, an OCMPA antenna 110, and user devices 112-1, 112-2,and 112-3 (collectively “user devices 112” and generically “user device112”).

Network 102 may include one or more wireless networks of any type, suchas, for example, a local area network (LAN), a wide area network (WAN),and a wireless satellite network, and/or one or more wireless publicland mobile networks (PLMNs). The PLMN(s) may be a Code DivisionMultiple Access (CDMA) PLMN, a Global System for Mobile Communications(GSM) PLMN, a Long Term Evolution (LTE) PLMN and/or other types of PLMNsnot specifically described herein (e.g., 5G PLMN networks).

Portions of network 102 may support Internet Protocol (IP)-basedcommunications, and may include, for example, an IP Multimedia Subsystem(IMS) network, which may provide voice and multimedia services to userdevices 112 based on Session Initiation Protocol (SIP).

As shown, network 102 includes a base station 104, which has an antenna104-1 and an optical transmitter 104-2. Antenna 104-1 transmits to andreceives radio signals from user devices 112 over a wirelesscommunication path that includes OCMPA antenna 110. For example, antenna104-1 may receive signals from user device 112-1 over wirelesscommunication link 118 and wireless communication link 114 via OCMPAantenna 110. Optical transmitter 104-2 sends optical control signals(e.g., laser beams) to a particular OCMPA antenna 110 through free spaceor optical media (e.g., optical fiber). The control signals direct OCMPAantenna 110 to modify the direction of its antenna pattern lobes, andthus, to focus on signals that are received from and/or transmitted in aparticular direction (e.g., to user device 112-1). When there aremultiple user devices 112 as shown in FIG. 1, the control signals directOCMPA antenna 110 to steer signal 114 to each of user devices 112 in atime-sliced manner.

Radio mount 106 may include a structure (e.g., a transmission tower) ora place (e.g., the rooftop of a high rise, the top of a hill, etc.)at/on which base station 104 and its components (i.e., antenna 104-1 andoptical transmitter 104-2) are mounted. Typically, radio mount 106 maybe located at a relatively high elevation, to allow antenna 104-1 and/oroptical transmitter 104-2 to have unobstructed views to one or moreOCMPA antenna 110.

OCMPA antenna mount 108 includes a structure of a place at which OCMPAantenna 110 may be affixed. In FIG. 1, OCMPA antenna mount 108 is shownas a street lamp post, but in practice, may include any other object orplace that is in the appropriate field of view for antenna 104-1.

OCMPA antenna 110 may relay radio frequency (RF) signals (e.g., signal114) from antenna 104-1 to user devices 112 as signals 118. In relayingthe RF signals, OCMPA antenna 110 may direct the main lobe of itsantenna pattern to a particular user device 112 in accordance withoptical control beam 116 from optical transmitter 104-2. Optical controlbeam 116 may be conveyed to OCMPA antenna 110 over the air (“freespace”) or through an optical medium (e.g., an optical fiber).

User device 112 may include an electronic device having communicationcapabilities. For example, user device 112 may include a cellularradiotelephone, a smart phone, a wearable computer (e.g., a wrist watch,eye glasses, etc.), a tablet, a set-top box (STB), a mobile phone, anytype of internet protocol (IP) communications device, a voice overinternet protocol (VoIP) device, a laptop computer, a palmtop computer,a gaming device, a media player device, or a digital camera thatincludes communication capabilities (e.g., wireless communicationmechanisms), a thing in the Internet-of-things IoT), etc. In a long-termevolution (LTE)-like environment, user device 112 may be referred to asuser equipment (UE).

In FIG. 1, the OCMPA antenna system includes base station 104 and OCMPAantenna 110. When in operation, base station 104 transmits signal 114and optical control beam 116 to OCMPA antenna 110 in the same timewindow. OCMPA antenna 110 passively deflects signal 114 to user device112. Optical control beam 116 controls the phased array antenna driverelements to control the direction at which OCMPA antenna 110 steerssignal 114.

As indicated above, OCMPA antenna 110 can be deployed at places wherecell density needs to be high. OCMPA antenna 110 is based onmeta-material technology to dynamically change its antennacharacteristics. OCMPA antenna 110 may be a passive device, and may beconstructed to be small and light. Deployment of the OCMPA antenna 110is easy, as it can be placed in locations where traditional wirelesssystems cannot be deployed. In the particular embodiment illustrated inFIG. 1, no fiber is needed to control or send signals to OCMPA antenna110. Additionally and/or alternatively, fiber and other opticalcomponents may be used to transmit the optical control signals toantenna 110.

Depending on the implementation, environment 100 may include additionalor fewer components than those illustrated in FIG. 1. For example, in adifferent embodiment, environment 100 may include additional userdevices, base stations, fiber interfaces and networks, OCMPA antennas,radio mounts, OCMPA antenna mounts, etc. In addition, objects in FIG. 1and the relative distances between them are not drawn to scale, and theymay be larger, smaller, and/or different in shape than depicted in FIG.1.

FIG. 2 illustrates an OCMPA antenna system 200. As shown, OCMPA antennasystem 200 includes base station 104 and OCMPA antenna 110, which arealso illustrated in FIG. 1. As further shown in FIG. 2, base station 104may include an Orthogonal Frequency Division Multiplex (OFDM) radio 202or other type of radio that uses a different modulation scheme (e.g.,Code Division Multiple Access (CDMA), OFDM-CDMA, Phase Shift Keying(PSK), Frequency Shift Keying (FSK), Quadrature Amplitude Modulation(QAM), etc.), an RF transceiver 204, an optical controller 206, a laserdriver 208, and a laser assembly 210.

OFDM radio 202 may receive a bitstream, process the bitstream for OFDMtransmission (e.g., serial-to-parallel conversion, encoding, applyingInverse Discrete Fourier Transform, parallel-to-serial conversion,cyclic prefix insertion, digital-to-analog conversion, modulation,etc.), and transmit OFDM radio signals corresponding to the inputbitstream. OFDM radio 202 may transmit the OFDM radio signals to RFtransceiver 204. Similarly, OFDM radio 202 may receive an output signalfrom RF transceiver 204, process the output signal to obtain a receivedbitstream (i.e., operations that are inverse of the operations performedfor transmission), and output the received bitstream.

In addition to transmitting/receiving OFDM signals, OFDM radio 202 maysend signals to optical controller 206. In one implementation, thesignals may provide information for beam steering (e.g., directions tosteer a beam to achieve greater signal strength, information to identifyan OCMPA antenna to steer RF signals, etc.).

RF transceiver 204 may receive OFDM radio signals from OFDM radio 202,demodulate and/or modulate the received signal at the desired carrierfrequency (e.g., a 5G frequency), and transmit the modulated signal asan unsteered beam 214 to OCMPA antenna 110.

Optical controller 206 may receive, from OFDM radio 202, signals thatinclude information for identifying an OCMPA antenna 110 to steer itsbeam to a particular user device 112. Based on the received signals fromOFDM radio 202, optical controller 206 may determine a direction tosteer beam 216. In some implementations, the signals may carryinformation that can be used determine the location of user device 112.Based on the location, optical controller 206 may identify a particularOCMPA antenna 110 that is to steer beam 216 to the particular userdevice 112, as well as a desired direction of OCMPA antenna 110 beam.

Based on the identity of OCMPA antenna 110 and the desired direction ofthe OCMPA antenna beam, optical controller 206 may apply laser driver208 to control laser assembly 210. More specifically, optical controller206 may direct the output of laser assembly 210 to the identified OCMPAantenna 110 and set the direction of OCMPA antenna beam through opticalcontrol beam 212.

Laser driver 208 may drive laser assembly 210 to direct optical controlbeam 212 to a particular OCMPA antenna 110 and/or to modulate the outputpower of laser assembly 210, such that optical control beam 212 causesthe identified/selected OCMPA antenna 110's main lobe (of its antennagain) to be directed at the user device 112.

Laser assembly 210 may receive the drive signals from laser driver 208.The drive signals may identify the particular OCMPA antenna 110 toreceive optical control beam 212, and may include directionalinformation for steering an OCMPA antenna beam 216. Laser assembly 210generates and transmits optical control beam 212 to OCMPA antenna 110.In one embodiment, optical control beam 212 may be composed ofindividual laser beams whose intensities vary across the cross-sectionof beam 212. The varying intensities of the individual laser beamsindicate, to OCMPA antenna 110, the direction to which beam 116 is to besteered. In a different embodiment, laser assembly 210 may not be partof base station 104 and may be external to base station 104.

In some implementations, laser assembly 210 may include multiple laseroutput ports, each of which corresponds to a particular OCMPA antenna110. Based on the drive signal, laser assembly 210 may select the outputport corresponding to the identified OCMPA antenna 110. In otherimplementations, laser assembly 210 may include mechanical and/orelectronic mechanisms for directing optical control beam 212 to theidentified/selected OCMPA antenna 110, over the air or through anoptical medium.

OCMPA antenna 110 receives optical control beam 212 from laser assembly210 and performs beam steering in accordance with the directioninformation provided in optical control beam 212. That is, OCMPA antenna110 deflects a received RF beam from base station 104 in accordance withintensities of individual laser beams that comprise optical control beam212. OCMPA antenna 110 deflects the RF signal to a target user device112.

Depending on the implementation, base station 104 and/or OCMPA antenna110 may include additional, fewer, different, and/or a differentarrangement of components than those illustrated in FIG. 2. For example,in one implementation, OFDM radio 202 may include a modulator thatdirectly transmits the OFDM signals to OCMPA antenna 110 at the desiredfrequencies. In such an implementation, base station 104 may not includeRF transceiver 204 as a separate component.

FIG. 3 illustrates exemplary components of OCMPA antenna 110. As shown,OCMPA antenna 110 may include a front panel 302 (e.g., printed circuitboard (PCB)), a rear panel 304 (e.g., a PCB), front antenna elements 306(e.g., copper patch elements), rear antenna elements 308 (e.g., copperpatch elements), vias 310, and electronic filter elements 312. Dependingon the implementation, OCMPA antenna 110 may include fewer, additional,different, or a differently arrangement of components than thoseillustrated in FIG. 3. For example, the relative sizes of components302-312 may be different from those illustrated in FIG. 3 (e.g., antennaelements with larger surface area, greater of smaller distances betweenantenna elements, etc.). In another example, OCMPA antenna 110 mayinclude additional antenna elements.

The array of front antenna elements 306 is similar or identical to rearantenna elements 308, although not illustrated in FIG. 3. Rear panel 304receives RF signals from base station 104 and passes the receivedsignals to front panel 302.

As shown, front and rear panels 302 and 304 provide electricallyinsulating bodies for mounting front and corresponding rear antennaelements 306 and 308 as a two-dimensional array. Each of front and rearantenna elements 306 and 308 is capable of both transmission andreception of radio signals.

Each front antenna element 306 makes an electrical contact to acorresponding electronic filter element 312 through vias 310, and acorresponding rear antenna element 308 makes an electrical contact tothe same electronic filter element 312 through vias 310. Thus, front andits corresponding rear antenna elements 306 and 308 are electricallycoupled, but through filter element 312, each of which functions as aphase shifting element (or “phase shifter”). In this configuration, RFsignals at the front antenna element 306 and the corresponding rearantenna element 308 differ by a phase angle corresponding to a delayassociated with filter element 312. Phase shifters 312 facilitate thesteering of the output beam, and are controlled by optical control beam212.

Each filter element 312 is capable of having its own state independentlyfrom other filter elements 312. Accordingly, if two rear copper patchelements 308 receive an RF signal from base station 104, and if thosetwo rear antenna elements 308 are coupled to respective filter elements312 with different states, the output signal values at the twocorresponding front antenna elements 306 would have different phaseshifts. That is, each filter element 312 serves as an independent phasedelay element.

The distance between adjacent antenna elements 306/308 may beapproximately on the order of or less than the wavelength correspondingto frequencies at which OCMPA antenna 110 operates (e.g., >14 GHz, <14GHz, between 1.8 and 2.5 GHz, between 2 to 8 GHz, etc.). The dimensionof the OCMPA antenna 110 may be approximately in the order of thewavelength times the number of antenna elements, although other sizesare possible depending on the required spaces for other components ofOCMPA antenna 110 which may render OCMPA antenna 110 be of any size.

FIG. 4A is a functional diagram of phase delay elements 402 of OCMPAantenna 110. As shown, phase delay element 402 includes a filter element312 (illustrated as a capacitor, although other filter elements arepossible) and a photodiode 404. Each filter element 312 is controlled bya corresponding photodiode 404. When photodiode 404 receives opticalcontrol signal 212, photodiode 404 provides a path to ground for filterelement 312, causing a phase shift between a signal arriving at rearpanel 304 and the signal output at front panel 302.

In FIG. 4A, if delay elements 402 are arranged as a linear array, asignal 410 through one filter element 312 is phase shifted relative to asignal 410 through a prior filter element 312. If the difference inphase angle between one element and an immediately prior element isdenoted Z, then Z determines the angle by which the main lobe of OCMPAantenna pattern is directed or steered. Accordingly, by controlling Z,an RF beam arriving at the rear of phased array antenna 110 can besteered to a particular user device 112.

Given a two dimensional array of antenna elements, as illustrated inFIG. 3, the phase delays between the elements occur in X and/or Ydirection, and accordingly, the beam can be directed in both X and Ydirections.

If an optical signal impinges evenly on the surface of rear panel 304(with antenna elements 308), the output RF signal on front panel 302will have a deflection angle of zero. If more optical energy is placedon some portions of rear panel 304 and less on the other portions, theoutput RF beam emerging from front panel 302 will have a deflectionangle proportional to the difference in the optical energy. Thedifferences in optical energy produces varying capacitance throughphotodiode 404-controlled filter elements 312 and thus varying phaseshifts on the RF output side (i.e., front panel 302).

FIGS. 4B and 4C illustrate exemplary positions of photodiodes 404 onrear panel 304. According to one embodiment shown in FIG. 4B, each ofphotodiodes 404 is positioned between adjacent rear antenna elements308. According to another embodiment in FIG. 4C, each photodiode 404 iscoupled to filter element/capacitor 312. In some implementations,photodiode-capacitor pairs (i.e., phase delay elements 402) can befabricated with an exposed optical area on a single silicon die ratherthan with two separate components.

FIGS. 5A-5D illustrate distributions of optical energy over the surface(shown in FIG. 4B) of rear panel 304 of OCMPA antenna 110. Asillustrated, it is possible to “paint” the surface with various powerpatterns to direct the antenna beam in specific ways.

In FIGS. 5A-5D, if more optical energy is applied to a particular area,quadrant, portion or region of the surface, more photodiodes 404 in thearea are activated, which in turn leads to greater capacitance inphoto-diode capacitor pairs 402 in the area, quadrant, portion orregion. Increased phase shifts at front and rear antenna elements causean outgoing RF beam (on front panel 302 of OCMPA antenna 110) to becontrolled and steered in the desired direction.

For example, FIG. 5A shows optical control beam 212 impinging on thecenter of the rear surface of OCMPA antenna 110, as indicated by thebrighter area. In this case, the output RF beam (i.e., the main lobe ofits gain pattern) from the front surface of OCMPA antenna does notchange its direction—no beam steering occurs.

FIG. 5B illustrates optical control beam 112 delivering most of itsenergy to the upper right corner of the rear surface of OCMPA antenna110, as indicated by the brighter area. The output RF beam is steeredtoward the upper right corner, for example, which is the upper leftcorner from the front view). As will be understood, depending on thecharacteristics of filter elements 402 different or alternative beampatterns may be achieved. FIGS. 5C and 5D depict optical control beam112 delivering most energy to, respectively, the right side of and thebottom of the rear surface of OCMPA antenna 110. In response, the beamis steered, respectively, in the desired directions.

FIG. 6 illustrates exemplary optical components of the OCMPA antennasystem 200. As shown, optical components may include a laser array 602and one or more lens 604.

Each laser in laser array 602 is individually controlled and can beswitched on and off at a high speed. By switching on or off differentgroupings of lasers in array 602, optical controller 206 may cause laserarray 602 to generate optical patterns similar to those illustrated inFIGS. 5A-5D. Laser driver 208 may provide the correct drivecurrent/voltage to each of the lasers to control optical signals.

Lens 604 focuses laser beams 606 from laser assembly 210, to direct thebeams to the rear surface of a selected OCMPA antenna 110.

Depending on the implementation, OCMPA antenna system 200 may includeadditional, fewer, different or a different arrangement of optical andcontrol components than those illustrated in FIG. 6. For example, in oneembodiment, system 200 may include components such as mirrors, opticalsplitter, multiplexer, demultiplexer, gratings, etc. In anotherembodiment, OCMPA antenna system 200 may include mechanical/electronicmechanisms for directing optical control beam 112 to a particular OCMPAantenna 110.

In another embodiment, an optical fiber may deliver optical control beam212 from laser array 602 to OCMPA antenna 110. If an optical fiber isused, it is possible to combine the laser output signals (each at adifferent frequency) through wave division multiplexing (WDM)techniques, to form a single optical control beam. When the opticalcontrol beam arrives at OCMPA antenna 110, the beam is demultiplexedinto multiple beams, each of which controls an optical delay element.Additionally and or alternatively, laser beams 606 and lens 604 may beused to distribute optical control beam 112 to control delay elements402.

Referring back to FIG. 1, base station 104 is shown as communicatingwith multiple user devices 112. This illustrates a simple use case, forOCMPA antenna system 200, in which base station 104 time slices itscommunication with each device 112. Each time base station 1104 selectsa user device 112 for communication, base station 104 directs aparticular OCMPA antenna 110 to steer its beam at user device 112. Whilethe beam is thus directed, base station 104 provides wirelesscommunication path to user device 112 for a time interval.

FIGS. 7-9 illustrate other use cases for OCMPA antenna system 200. InFIG. 7, base station 704 is located at the base of a tower 706. Thisparticular configuration may be used, for example, when there is alimited tower space or available weight loading. As further shown, basestation 704 may be coupled to not only OCMPA antenna 710-1, but alsoOCMPA antenna 710-2, which is affixed to a street lamp post. Accordingto one embodiment, base station 704 may include an optical port for eachof its feeder antennas 704-4 or 704-5, and base station 704 may selectthe port corresponding to an OCMPA antenna 710 that steers the RF signalto a particular user device 712. In a different embodiment, base station704 may include two sets of optical components (e.g., two sets of laserarrays), one for each feeder antenna 704-4 and 704-5. In yet anotherembodiment, base station 704 may include a mechanism for steeringoptical control beam 212 to one of many OCMPA antennas 710.

In FIG. 8, base station 804 is located at the rooftop of a building 802.Because of its location, base station 804 may feed a large number ofOCMPA antennas, such as antenna 810-1 and 810-2, both of which areaffixed to utility poles/lamp posts.

FIG. 9 illustrates a use case in which base station 904 at building902-1 selects a OCMPA antenna 910 to relay RF signals around a building902-2. In this embodiment, selecting a particular OCMPA antenna 910requires knowing the location of user devices 912 as well as thelocations of possible obstructions. Optical controller 206 may includeadditional components (e.g., a computational device) to identify thebest OCMPA antenna for the beam steering.

FIG. 10 is a flow diagram of an exemplary process 1000 that isassociated with OCMPA antenna system 200. Process 1000 may be performedby one or more components of OCMPA antenna system 200, such as basestation 104, OCMPA antenna 110, for example.

Process 1000 may include receiving an input bit stream that is to betransmitted to a user device (block 1002). For example, an OFDM radio202 or another type of modulator in base station 104 may receive a bitstream that is to be transmitted to user device 112.

Process 1000 may further include generating OFDM signals that are to bemodulated and then transmitted to a user device (block 1004). Forexample, OFDM radio 202 may process the bit stream and generate OFDMsignals.

Process 1000 may also include generating signals, from which an OCMPAantenna (which is to receive the generated OFDM signal) can beidentified; and from which a beam steering direction can be determined(block 1006). For example, OFDM radio 202 may provide a signal tooptical controller 206. Based on the signal, optical controller 206 mayidentify a specific OCMPA antenna 110 that is to receive the OFDMsignal, and the beam steering direction for the identified OCMPA antenna110.

Process 1000 may further include selecting an OCMPA antenna anddetermining the direction of beam steering for the selected antenna(block 1008), as well as directing an optical control beam to theselected OCMPA antenna, and at the same time, modulating the generatedOFDM signal and transmitting the modulated OFDM signal to the OCMPAantenna (block 1010). For example, optical controller 206 may select anOCMPA antenna 110 for user device 112 and determine the direction ofbeam steering. Thereafter, optical controller 206 may send (via laserdriver 208) optical control beam 212 to OCMPA antenna 110. At the sametime that optical controller 206 transmits optical control beam 212 frombase station 104, RF transceiver 204 modulates the OFDM signal andtransmits the modulated OFDM signal to OCMPA antenna 110. In oneembodiment, RF transceiver 204 may transmit the OFDM signal duringtransmissions of the optical control beam may occur over the same timeperiod. In embodiments where an OCMPA antenna can store (at leasttemporarily) the directional information conveyed by the optical controlbeam, RF transceiver 204 may transmit the OFDM signal either during orafter the transmission of the optical control beam.

Process 1000 may include steering the modulated OFDM signal to a userdevice (block 1012). For example, when OCMPA antenna 110 receivesoptical control beam 212 and the modulated OFDM signal from base station104, OCMPA antenna 110 may steer the modulated OFDM signal to userdevice 112 in accordance with the directional information provided byoptical control beam 212.

In this specification, various preferred embodiments have been describedwith reference to the accompanying drawings. It will be evident thatmodifications and changes may be made thereto, and additionalembodiments may be implemented, without departing from the broader scopeof the invention as set forth in the claims that follow. Thespecification and drawings are accordingly to be regarded in anillustrative rather than restrictive sense.

For example, rather than constructing OCMPA antenna 110 usingphotodiode-capacitor pairs as phase delay elements, it is possible touse photo-varactor diodes to provide for creating phase delays necessaryfor beam steering. In another example, OCMPA antenna 110 may beconstructed to have two separate panels for a downlink and uplinkfrom/to base station 104. In some implementations, OCMPA antenna 110 mayinclude low power amplifiers, to provide amplification of RF signals inan uplink/downlink signal paths from user device 112 to base station104.

In yet another example, base station 104 may use RF signals rather thanoptical signals (e.g., about 80 GHz) to steer beams at deflectorantennas. In still yet another example, base station 104 may include afeeder antenna that is itself a phased array antenna, and is capable ofdirecting its control beam to the selected deflector antenna.

In the above, while a series of blocks have been described with regardto the processes illustrated in FIG. 10, the order of the blocks may bemodified in other implementations. In addition, non-dependent blocks mayrepresent blocks that can be performed in parallel.

It will be apparent that aspects described herein may be implemented inmany different forms of software, firmware, and hardware in theimplementations illustrated in the figures. The actual software code orspecialized control hardware used to implement aspects does not limitthe invention. Thus, the operation and behavior of the aspects weredescribed without reference to the specific software code—it beingunderstood that software and control hardware can be designed toimplement the aspects based on the description herein.

To the extent the aforementioned embodiments collect, store or employpersonal information provided by individuals, it should be understoodthat such information shall be used in accordance with all applicablelaws concerning protection of personal information. The collection,storage and use of such information may be subject to consent of theindividual to such activity, for example, through well known “opt-in” or“opt-out” processes as may be appropriate for the situation and type ofinformation. Storage and use of personal information may be in anappropriately secure manner reflective of the type of information, forexample, through various encryption and anonymization techniques forparticularly sensitive information.

No element, block, or instruction used in the present application shouldbe construed as critical or essential to the implementations describedherein unless explicitly described as such. Also, as used herein, thearticles “a”, “an” and “the” are intended to include one or more items.Further, the phrase “based on” is intended to mean “based, at least inpart, on” unless explicitly stated otherwise.

What is claimed is:
 1. A system comprising: a base station comprising: alaser assembly that transmits an optical control beam to a phased arrayantenna external to and remote from the base station; and a radiofrequency (RF) transceiver that transmits a radio signal to the phasedarray antenna, wherein the phased array antenna deflects the radiosignal arriving at the phased array antenna in a particular directionindicated by the optical control beam, and wherein the particulardirection of the deflected radio signal is toward a particular userdevice.
 2. The system of claim 1, wherein the laser assembly transmitsthe optical control beam to the phased array antenna over a first timeperiod; wherein the RF transceiver transmits the radio signal over asecond time period; and wherein the first time period begins before orat a same time that the second time period begins and the first timeperiod ends after or at a same time that the second time period ends. 3.The system of claim 1, wherein the radio signal includes an OrthogonalFrequency Division Multiplexing (OFDM) signal over a Fifth Generation(5G) carrier.
 4. The system of claim 3, wherein the base station furtherincludes: an OFDM module that receives an input bit stream, processesthe bit stream, and outputs feed signals having orthogonal subcarriersto the RF transceiver and outputs optical control signals; and anoptical controller that receives the optical control signals to controlthe laser assembly to generate the optical control beam.
 5. The systemof claim 4, wherein the laser assembly includes an array of lasers, andwhen the optical controller controls the laser assembly, the opticalcontroller causes the laser assembly to set an intensity of each laserbeam generated by the array of lasers.
 6. The system of claim 5, whereineach laser of the array of lasers generates a laser beam at a frequencydifferent from frequencies of laser beams from other lasers in the arrayof lasers, wherein the laser assembly includes one or more opticalmultiplexers to combine the laser beams from the array of lasers into asingle beam.
 7. The system of claim 4, wherein the optical controlsignals include information for the optical controller to determine adeflection angle for the radio signal to be in the particular direction;and wherein the optical controller determines the particular directionbased on the optical control signals and causes the optical control beamto indicate the particular direction to the phrased array antenna. 8.The system of claim 4, wherein the optical control signals includeinformation used to select, by the optical controller, the phased arrayantenna, from a plurality of phased array antennas; and wherein theoptical controller directs the optical control beam to the selectedphased array antenna.
 9. The system of claim 1, further comprising thephrased array antenna, wherein the phased array antenna includes: a rearpanel comprising: a first array of phase shift elements; and a secondarray of rear antenna elements; a front panel comprising: a third arrayof front antenna elements, wherein each of the front antenna elements iselectrically coupled to a corresponding one of the rear antenna elementsthrough one of the phase shift elements, and wherein when the secondarray of rear antenna elements receives the radio signal, from the basestation and the first array of phase shift elements receives the opticalcontrol beam from the base station, the third array of front antennaelements transmits the deflected radio signal in the particulardirection.
 10. The system of claim 9, wherein the phase shift elementsinclude photodiode and capacitor pairs.
 11. The system of claim 9,wherein the phase shift elements include: photo-varactor diodes.
 12. Thesystem of claim 9, wherein each of the rear antenna elements and frontantenna elements includes a patch of conducting material.
 13. The systemof claim 9, wherein each of the rear panel and front panel includes aprinted circuit board (PCB).
 14. The system of claim 9, wherein each ofthe rear antenna elements includes an electrical contact to one of thephase shift elements.
 15. The system of claim 9, wherein the first arrayof phase shift elements receives the optical control beam from the basestation through an optical fiber.
 16. The system of claim 9, wherein thewavelength of the radio signal is less than about 20 millimeters.
 17. Amethod comprising: receiving a bit stream; processing the bit stream tooutput feed signals to a radio frequency (RF) transceiver to generate anRF signal; outputting optical control signals to control a laserassembly to transmit an optical control beam; and transmitting theoptical control beam and the RF signal to the phased array antenna,wherein the optical control beam includes information that indicates aparticular direction in which the phased array antenna is to deflect theradio signal.
 18. The method of claim 17, wherein outputting the opticalcontrol signals to control the laser assembly includes: determining,based on information included in the optical control signals, theparticular direction.
 19. The method of claim 17, wherein transmittingthe optical control beam includes: generating a plurality of laserbeams; setting, for each of the laser beams to be generated by the arrayof lasers, an intensity of the laser beam.
 20. The method of claim 19,wherein transmitting the optical control beam further includes:optically multiplexing one or more of the laser beams to generate theoptical control beam.